System and method for fuel cell material x-ray analysis

Abstract

An imaging technology for fuel cells is based on x-ray microscopy. A metrology system images the electro-chemical interaction areas of solid-oxide fuel cells (SOFC) in-situ. This system takes advantage of both the penetrating power and elemental absorption contrast of hard x-ray radiation to image the internal interaction areas in a SOFC. The technology can further take advantage of the strong dependence of the x-ray absorption on material type and energy to distinguish the four major material types: cathode, electrolyte, air, and low-Z contaminants such as sulfur.

1. A system for imaging structures of fuel cells, comprising:
 an x-ray source for generating x rays; 
 a sample stage for holding fuel cell material; 
 a chamber for containing the fuel cell material; 
 an x-ray objective lens for collecting and focusing the x-rays passing through the fuel cell material; and 
 a detector for detecting the x-rays from the x-ray lens. 
 
   
   
     2. A system claimed in  claim 1 , wherein the fuel cell material is mounted on a rotation stage to facilitate tomographic data acquisition. 
   
   
     3. A system claimed in  claim 2 , where fuel cell material is rotated by the rotation stage to acquire images at different rotation angles to obtain projection images needed for tomography data reconstruction. 
   
   
     4. A system claimed in  claim 1 , wherein the x-ray source comprises an electron source for generating an electron beam directed at a metal anode target, the electron beam generating x-rays in the metal layer. 
   
   
     5. A system claimed in  claim 4 , wherein the anode comprises copper. 
   
   
     6. A system claimed in  claim 4 , wherein the anode comprises molybdenum. 
   
   
     7. A system claimed in  claim 4 , wherein the source is a source system comprising two or more different targets for generating x-rays at different energy levels. 
   
   
     8. A system claimed in  claim 7 , wherein one of the targets is copper and another is molybdenum. 
   
   
     9. A system claimed in  claim 1 , wherein the chamber contains the fuel cell material along with fluids or gases enabling the fuel cell material to operate to convert chemical energy directly into electrical energy. 
   
   
     10. A system claimed in  claim 9 , wherein the chamber comprises one or more window structures through which the x-ray pass to access a region of interest of the fuel cell material. 
   
   
     11. A system claimed in  claim 9 , further comprising two window structures on either side of the chamber, the x-rays being directed to pass through the two window structures on the path between the x-ray source and the detector. 
   
   
     12. A system claimed in  claim 9 , further comprising fuel and exhaust tubes to the chamber for providing fuel to the fuel cell and removing exhaust from the fuel cell during the detection of the x-rays by the detector. 
   
   
     13. A system claimed in  claim 1 , wherein the source comprises an electron source for generating an electron beam directed at two or more metal anode targets, the electron beam generating x-rays in metal layers of the targets to generate x-rays at different energy levels, combining image data from the different energy levels to identify materials in the fuel cell. 
   
   
     14. A method for imaging fuel cells, comprising:
 generating x rays; 
 holding fuel cell material in the x rays; 
 collecting and focusing the x-rays passing through the fuel cell material; and 
 detecting the collected and focused x-rays from the fuel cell material to form an image. 
 
   
   
     15. A method claimed in  claim 14 , further comprising rotating the fuel cell material while acquiring images at different rotation angles to obtain projection images for tomography data reconstruction. 
   
   
     16. A method claimed in  claim 14 , further comprising providing one or more windows structures through which the x-ray pass to access a region of interest of the fuel cell material. 
   
   
     17. A method claimed in  claim 16 , further comprising rotating the fuel cell material while acquiring images at different rotation angles while the fuel cell material is converting chemical energy directly into electrical energy to obtain projection images for tomography data reconstruction. 
   
   
     18. A method claimed in  claim 14 , further comprising operating the fuel cell material to convert chemical energy directly into electrical energy while detecting the x-rays to generate images of the operating fuel cell. 
   
   
     19. A method claimed in  claim 14 , further comprising providing two window structures on either side of the chamber, the x-rays being directed to pass through the two window structures on path through the fuel cell material. 
   
   
     20. A method claimed in  claim 14 , further comprising piping fuel and exhaust to and from the fuel cell during the detection of the x-rays to generate images of the operating fuel cell. 
   
   
     21. A method claimed in  claim 14 , wherein generating the x-rays comprises generating an electron beam directed at two or more metal anode targets, the electron beam generating x-rays in metal layers of the targets to generate x-rays at different energy levels, and the method further comprises combining image data from the different energy levels to identify materials in the fuel cell.